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Background: Erythromelalgia, which has primary and secondary presentations, causes heat, pain, and redness in the skin. The condition seems to have an autonomic basis, with vasomotor dysfunction causing dilatation of some blood vessels and constriction of others. No consistently effective treatments have been reported. Anticonvulsant, antidepressant, antihistamine, anti-inflammatory, antihypertensive, analgesic, nutritional, and topical approaches have been tried as were lidocaine infusions, nerve blocks, and thoracic and lumbar sympathectomies. Interosseous membrane stimulation appears to affect the local autonomic milieu in the extremity being treated. This approach was used on a patient with erythromelalgia., Case: A 36-year-old woman with erythromelalgia was treated with interosseous membrane stimulation. Eight treatments were given over a 1-year timeframe at 1-3-month intervals., Results: This patient repeatedly experienced much relief from her burning paresthesias, swelling, diaphoresis, and ruddy discoloration of her extremities for 6-8 hours following each treatment. The intensity of her discomfort subsided gradually over time., Conclusions: Interosseous membrane stimulation is a safe, simple, and effective treatment for erythromelalgia, which is notoriously refractory to treatment. This patient's response to treatment might have been a result of localized derangement of her autonomic nervous system. It is possible that manipulation of the autonomic milieu of an extremity is a significant factor in the mechanism of action of interosseous membrane stimulation., Competing Interests: No financial conflicts of interest exist., (Copyright 2024, Mary Ann Liebert, Inc., publishers.)

The Izu-Bonin-Mariana (IBM) fore arc preserves igneous rock assemblages that formed during subduction initiation circa 52 Ma. International Ocean Discovery Program (IODP) Expedition 352 cored four sites in the fore arc near the Ogasawara Plateau in order to document the magmatic response to subduction initiation and the physical, petrologic, and chemical stratigraphy of a nascent subduction zone. Two of these sites (U1440 and U1441) are underlain by fore-arc basalt (FAB). FABs have mid-ocean ridge basalt (MORB)-like compositions, however, FAB are consistently lower in the high-field strength elements (TiO 2 , P 2 O 5 , Zr) and Ni compared to MORB, with Na 2 O at the low end of the MORB field and FeO* at the high end. Almost all FABs are light rare earth element depleted, with low total REE, and have low ratios of highly incompatible to less incompatible elements (Ti/V, Zr/Y, Ce/Yb, and Zr/Sm) relative to MORB. Chemostratigraphic trends in Hole U1440B are consistent with the uppermost lavas forming off axis, whereas the lower lavas formed beneath a spreading center axis. Axial magma of U1440B becomes more fractionated upsection; overlying off-axis magmas return to more primitive compositions. Melt models require a two-stage process, with early garnet field melts extracted prior to later spinel field melts, with up to 23% melting to form the most depleted compositions. Mantle equilibration temperatures are higher than normal MORB (1,400 °C-1,480 °C) at relatively low pressures (1-2 GPa), which may reflect an influence of the Manus plume during subduction initiation. Our data support previous models of FAB origin by decompression melting but imply a source more depleted than normal MORB source mantle.

OBJECTIVE To evaluate the agreement between results of microscopic examination and bacterial culture of bile samples from dogs and cats with hepatobiliary disease for detection of bactibilia. DESIGN Cross-sectional study. ANIMALS 31 dogs and 21 cats with hepatobiliary disease for which subsequent microscopic examination and bacterial culture of bile samples was performed from 2004 through 2014. PROCEDURES Electronic medical records of included dogs and cats were reviewed to extract data regarding diagnosis, antimicrobials administered, and results of microscopic examination and bacterial culture of bile samples. Agreement between these 2 diagnostic tests was assessed by calculation of the Cohen κ value. RESULTS 17 (33%) dogs and cats had bactibilia identified by microscopic examination of bile samples, and 11 (21%) had bactibilia identified via bacterial culture. Agreement between these 2 tests was substantial (percentage agreement [positive and negative results], 85%; κ = 0.62; 95% confidence interval, 0.38 to 0.89) and improved to almost perfect when calculated for only animals that received no antimicrobials within 24 hours prior to sample collection (percentage agreement, 94%; κ = 0.84; 95% confidence interval, 0.61 to 1.00). CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that agreement between microscopic examination and bacterial culture of bile samples for detection of bactibilia is optimized when dogs and cats are not receiving antimicrobials at the time of sample collection. Concurrent bacterial culture and microscopic examination of bile samples are recommended for all cats and dogs evaluated for hepatobiliary disease.

Pneumonia caused by Mannheimia haemolytica is an important disease of cattle (BO), domestic sheep (DS, Ovis aries) and bighorn sheep (BHS, Ovis canadensis). Leukotoxin (Lkt) produced by M. haemolytica is cytolytic to all leukocyte subsets of these three species. Although it is certain that CD18, the beta subunit of beta(2) integrins, mediates Lkt-induced cytolysis of leukocytes, whether CD18 of all three beta(2) integrins, LFA-1 (CD11a/CD18), Mac-1 (CD11b/CD18) and CR4 (CD11c/CD18), mediates Lkt-induced cytolysis of BO, DS and BHS leukocytes remains a controversy. Based on antibody inhibition experiments, earlier studies suggested that LFA-1, but not Mac-1 and CR-4, serves as a receptor for M. haemolytica Lkt. PMNs express all three beta(2) integrins, and they are the leukocyte subset that is most susceptible to Lkt. Therefore we hypothesized that all three beta(2) integrins serve as the receptor for Lkt. The objective of this study was to determine whether Mac-1 of BO, DS and BHS serves as a receptor for Lkt. cDNAs for CD11b of BO, DS and BHS were transfected into a Lkt-non-susceptible cell line along with cDNAs for CD18 of BO, DS and BHS, respectively. Transfectants stably expressing BO, DS or BHS Mac-1 specifically bound Lkt. These transfectants were lysed by Lkt in a concentration-dependent manner. Increase in intracellular [Ca(2+)](i) was observed in transfectants following exposure to low concentrations of Lkt indicating signal transduction through secondary messengers. Collectively, these results indicate that Mac-1 from these three species serves as a receptor for M. haemolytica Lkt.

When a fixed anode x-ray tube is placed in a magnetic field (B) that is parallel to the anode-cathode axis, the x-ray exposure increases with increasing B. It was hypothesized that the increase was caused by backscattered electrons which were constrained by B and reaccelerated by the electric field onto the x-ray tube target. We performed computer simulations and physical experiments to study the behavior of the backscattered electrons in a magnetic field, and their effects on the radiation output, x-ray spectrum, and off-focal radiation. A Monte Carlo program (EGS4) was used to generate the combined energy and angular distribution of the backscattered electrons. The electron trajectories were traced and their landing locations back on the anode were calculated. Radiation emission from each point was modeled with published data (IPEM Report 78), and thus the exposure rate and x-ray spectrum with the contribution of backscattered electrons could be predicted. The point spread function for a pencil beam of electrons was generated and then convolved with the density map of primary electrons incident on the anode as simulated with a finite element program (Opera-3d, Vector Fields, UK). The total spatial distribution of x-ray emission could then be calculated. Simulations showed that for an x-ray tube working at 65 kV, about 54% of the electrons incident on the target were backscattered. In a magnetic field of 0.5 T, although the exposure would be increased by 33%, only a small fraction of the backscattered electrons landed within the focal spot area. The x-ray spectrum was slightly shifted to lower energies and the half value layer (HVL) was reduced by about 6%. Measurements of the exposure rate, half value layer and focal spot distribution were acquired as functions of B. Good agreement was observed between experimental data and simulation results. The wide spatial distribution of secondary x-ray emission can degrade the MTF of the x-ray system at low spatial frequencies for B < 0.5 T.

The Disproportionate micromelia (Dmm) mouse has a three nucleotide deletion in Col2a1 in the region encoding the C-propeptide which results in the substitution of one amino acid, Asn, for two amino acids, Lys-Thr. Western blot and immunohistochemical analyses failed to detect type II collagen in the cartilage matrix of the homozygous mice and showed reduced levels in the matrix of heterozygous mice. Type II collagen chains localized intracellularly within the chondrocytes of homozygote and heterozygote tissues. These findings provide evidence that the expression of type II procollagen chains containing the defective C-propeptide results in an intracellular retention and faulty secretion of type II procollagen molecules. A complete absence of mature type II collagen from the homozygote cartilage and an insufficiency of type II collagen in the heterozygote cartilage explains the Dmm mouse phenotype. The integrity of the C-propeptide is thus crucial for the biosynthesis of normal type II collagen by chondrocytes.

Optimum shielding of the radiation from particle accelerators requires knowledge of the attenuation characteristics of the shielding material. The most common material for shielding this radiation is concrete, which can be made using various materials of different densities as aggregates. These different concrete mixes can have very different attenuation characteristics. Information about the attenuation of leakage photons and neutrons in ordinary and heavy concrete is, however, very limited. To increase our knowledge and understanding of the radiation attenuation in concrete of various compositions, we have performed measurements of the transmission of leakage radiation, photons and neutrons, from a Varian Clinac 2100C medical linear accelerator operating at maximum electron energies of 6 and 18 MeV. We have also calculated, using Monte Carlo techniques, the leakage neutron spectra and its transmission through concrete. The results of these measurements and calculations extend the information currently available for designing shielding for medical electron accelerators. Photon transmission characteristics depend more on the manufacturer of the concrete than on the atomic composition. A possible cause for this effect is a non-uniform distribution of the high-density aggregate, typically iron, in the concrete matrix. Errors in estimated transmission of photons can exceed a factor of three, depending on barrier thickness, if attenuation in high-density concrete is simply scaled from that of normal density concrete. We found that neutron transmission through the high-density concretes can be estimated most reasonably and conservatively by using the linear tenth-value layer of normal concrete if specific values of the tenth-value layer of the high-density concrete are not known. The reason for this is that the neutron transmission depends primarily on the hydrogen content of the concrete, which does not significantly depend on concrete density. Errors of factors of two to more than ten, depending on barrier thickness, in the estimated transmission of neutrons through high-density concrete can be made if the attenuation is scaled by density from normal concrete.

The radiation safety system of the B-Factory accelerator facility at the Stanford Linear Accelerator Center is described. The radiation safety system, which is designed to protect people from prompt radiation exposure due to beam operation, consists of the access control system and the radiation containment system. The access control system prevents people from being exposed to the very high radiation levels inside a beamline shielding enclosure. The access control system consists of barriers, a standard entry module at every entrance, and beam stoppers. The radiation containment system prevents people from being exposed to the radiation outside a shielding enclosure due to either normal or abnormal operation. The radiation containment system consists of power limiting devices, shielding, dump and collimator, and an active radiation monitoring system. The inter-related elements for the access control system and radiation containment system, as well as the associated interlock network, are described. The policies and practices used in establishing the radiation safety system are also compared with the regulatory requirements.

Human performance plays a significant role in the development and operation of any complex system, and human errors are significant contributors to degraded performance, incidents, and accidents for technologies as diverse as medical systems, commercial aircraft, offshore oil platforms, nuclear power plants, and space systems. To date, serious accidents attributed to human error have fortunately been rare in space operations. However, as flight rates go up and the duration of space missions increases, the accident rate could increase unless proactive action is taken to identity and correct potential human errors in space operations. The Idaho National Engineering and Environmental Laboratory (INEEL) has developed and applied structured methods of human error analysis to identify potential human errors, assess their effects on system performance, and develop strategies to prevent the errors or mitigate their consequences. These methods are being applied in NASA-sponsored programs to the domain of commercial aviation, focusing on airplane maintenance and air traffic management. The application of human error analysis to space operations could contribute to minimize the risks associated with human error in the design and operation of future space systems.

We have simulated the head geometry of a Varian Clinac 2100C/2300C medical accelerator in a Monte Carlo calculation to produce photoneutrons and transport them through the head shielding into a typical therapy room (modeled by a test cell at Varian Associates). The fast neutron leakage fluence and energy spectra have been calculated at 7 positions around the linac head for typical beam operation at 10, 15, 18 and 20 MV. The results of these calculations have been compared with limited measurements made using the same model accelerator operating in a Varian test cell. Calculations were also made for the fluence and energy spectra outside the head with no surrounding concrete walls, floor or ceiling to eliminate the effects of scattering from concrete. Comparisons were also made with calculations using a much simplified head geometry. The results indicate that the calculations using the complex head geometry compare, within the uncertainties, with the measurements. The simple head geometry leads to differences of a factor of 2 from the complex geometry. Results of these calculations can be used to calculate fast neutron transmission through various shielding configurations and through labyrinths.

The photoneutron yields produced in different components of the medical accelerator heads evaluated in these studies (24-MV Clinac 2500 and a Clinac 2100C/2300C running in the 10-MV, 15-MV, 18-MV and 20-MV modes) were calculated by the EGS4 Monte Carlo code using a modified version of the Combinatorial Geometry of MORSE-CG. Actual component dimensions and materials (i.e., targets, collimators, flattening filters, jaws and shielding for specific accelerator heads) were used in the geometric simulations. Calculated relative neutron yields in different components of a 24-MV Clinac 2500 were compared with the published measured data, and were found to agree to within +/-30%. Total neutron yields produced in the Clinac 2100/2300, as a function of primary electron energy and field size, are presented. A simplified Clinac 2100/2300C geometry is presented to calculate neutron yields, which were compared with those calculated by using the fully-described geometry.

The Final Focus Test Beam (FFTB) is a new beam line at the Stanford Linear Accelerator Center designed to test new beam optics concepts, hardware, and techniques necessary to achieve and measure the small spot sizes required for future generations of high-energy e+e- linear colliders. The FFTB takes a 47 GeVc-1, 1 kW electron beam at the end of the Stanford Linear Accelerator Center linear accelerator and transports it to the FFTB beam dump. A radiation protection system was designed and installed for the FFTB with the primary goal that the integrated dose equivalent outside the shielding resulting from beam loss would not exceed 10 mSv y-1. This system is comprised of shielding, a beam containment system and a personnel protection system. This paper presents various aspects of radiation safety at Stanford Linear Accelerator Center that were considered in the design of the FFTB radiation protection system. Beam tests were conducted in which the performance of various beam containment devices and the shielding effectiveness were evaluated. Preliminary results from these tests are presented.

This paper characterizes the functional dependence of the giant dipole resonance neutron yield produced by electrons in terms of the atomic number (Z) and thickness (T) of the target. The yields were calculated by integrating, over the photon energy, the product of the differential photon track length and published photoneutron cross sections. The EGS4 Monte Carlo code and analytical formulas were used to calculate the differential photon track length. In thick targets, the Giant Dipole Resonance neutron yield approaches a saturation value as target thickness T increases to 10 radiation lengths. A formula, 8 x 10(-6) x (Z1/2 + 0.12 Z3/2 - 0.001 Z5/2) n electron-1 MeV-1, developed from EGS4 calculations, estimates thick-target neutron yields for incident electron energies Eo above 50 MeV. Giant dipole resonance neutron yields, calculated by several analytic formulas for the differential photon track length, are compared with EGS4 calculations. Modifications to the analytic formulas are suggested. A scaling function is derived to estimate, from the thick-target formula, neutron yields produced in thin targets.

The EGS4 electron-photon Monte Carlo code has been used to study the characteristics of the bremsstrahlung x rays generated from the interaction of circulating electrons with the residual gas in accelerator storage rings. Gas bremsstrahlung dose rates are given for various opening angles as a function of the electron beam energy ranging from 0.5-10 GeV. Photon and neutron dose rates, generated from various devices struck by gas bremsstrahlung in a synchrotron radiation beamline, are also presented along with the photon spectral and transmission results. The EGS4-predicted results are found to be in basic agreement with the measurements made at the Stanford Synchrotron Radiation Laboratory. Figures, equations, and a simple method useful for the photon-neutron shielding design for beamlines are provided.

Axillary metastases from squamous cell carcinomas of the head and neck are usually considered signs of incurability. A case is presented in which the patient developed well-differentiated squamous cell carcinoma in bilateral axillary nodes following total laryngectomy and radical neck dissection for advanced recurrent squamous cell carcinoma of the larynx. Bilateral axillary dissection was performed on this patient followed by a second neck dissection for metastasis. The patient remained well for 25 years free of disease, dying of a massive heart attack. One report of this phenomenon has been found in the literature. The authors conclude that radical axillary dissection should be considered in selective cases of well-differentiated carcinoma in axillary nodes from a controlled primary in the head and neck mucosa when no other signs of dissemination have been found. A brief review of cervical and axillary lymphatic anatomy is included.

Objectives and Rationale: For 10 common clinical presentations, we assessed differences in physicians' utilization of and charges for diagnostic imaging, depending on whether they performed imaging examinations in their offices (self-referral) or referred their patients to radiologists (radiologist-referral)., Methods: Using previously developed methodologies, we generated episodes of medical care from an insurance claims database. Within each episode, we determined whether diagnostic imaging had been performed, and if so, whether by a self-referring physician or a radiologist. For each of the 10 clinical presentations, we compared the mean imaging frequency, mean imaging charges per episode of care, and mean imaging charges for diagnostic imaging attributable to self- and radiologist-referral., Results: Depending on the clinical presentation, self-referral resulted in 1.7 to 7.7 times more frequent performance of imaging examinations than radiologist-referral (P < .01, all presentations). Within all physician specialties, self-referral uniformly led to significantly greater utilization of diagnostic imaging than radiologist-referral. Mean imaging charges per episode of medical care (calculated as the product of the frequency of utilization and mean imaging charges) were 1.6 to 6.2 times greater for self-referral than for radiologist-referral (P < .01, all presentations). When imaging examinations were performed--including those performed in both physicians' offices and hospital outpatient departments--mean imaging charges were significantly greater for radiologists than for self-referring physicians in seven of the clinical presentations (P < .01). This result is related to the high technical charges of hospital outpatient departments; in office practice, radiologists' mean charges for imaging examinations were significantly less than those of self-referring physicians for seven clinical presentations (P < .01)., Conclusions: Nonradiologist physicians who operate diagnostic imaging equipment in their offices perform imaging examinations more frequently, resulting in higher imaging charges per episode of medical care. These results extend our previous research on this subject by their focus on a broader range of clinical presentations; a mostly elderly, retired population; and the inclusion of higher-technology imaging examinations.

To better define the management and behavior of carotid body tumors, a 34-year surgical experience with 33 tumors in 30 patients was reviewed. There were 20 women and 10 men with an age range of 20 to 78 years. All but one presented with a neck mass. Arteriography was performed on 21 patients and was diagnostic in every case. There was no surgical mortality. Complications occurred in eight patients (27%), and one long-term neurologic deficit occurred. Three of 33 tumors were malignant, and aggressive resection of all approachable disease with radiotherapy for unresectable metastases led to prolonged survival in each case. Carotid body tumors present with neck mass. Arteriography is diagnostic and surgery is indicated. Even for malignant tumors and metastases, aggressive resection and radiotherapy are indicated.

The authors examined the patterns of injury and death rates of patients involved in vehicle-related accidents who were admitted to the Regional Trauma Unit of Sunnybrook Health Science Centre in Toronto. Information was collected prospectively over a 36-month period. The subjects were placed in one of three mechanism-of-injury categories: four-wheel passenger vehicles, motorcycles and pedestrians. The patterns of injury were classified as primarily to the craniofacial and neck area, the torso, the extremities or to multiple regions. There were 815 patients who were involved in vehicle-related crashes and who suffered moderate to severe injuries (at least one region scoring more than 3 on the abbreviated injury scale). The death rate was 13% overall but was 21% in the group receiving multiple injuries. By mechanism of injury the death rates were: pedestrian group 20%, motorcycle group 18% and passenger-vehicle group 11% (p less than 0.01, chi 2 analysis). There was no difference in the mean injury severity score among the mechanism of injury groups. A higher proportion of the passenger-vehicle group sustained isolated craniofacial and torso injuries, and the pedestrian and motorcycle groups sustained more extremity injuries (p less than 0.001, chi 2 analysis). The results reveal a clear association between mechanism of injury and the patterns of injury observed.

As delay in diagnosing unstable cervical spine injuries unnecessarily exposes patients to risk of neurologic injury, it is often recommended that complex radiologic investigations be performed on alert patients with neck pain, tenderness, or neurologic deficit despite normal plain radiographs. The optimal investigation of patients unable to reliably provide such information is less clear. How many X-rays are enough to clear the cervical spine? In order to answer this question, a retrospective review of 775 motor vehicle crash (MVC) victims was conducted. Ninety-two (12%) sustained cervical spine injury. Sixteen of these injuries were missed initially and, in a further 18 cases, the lateral cervical spine X-ray was wrongly interpreted as positive. Fifty-five per cent of patients with cervical injury had a Glasgow Coma Score (GCS) of less than 15 on admission. Lateral radiographic visualization of the complete cervical spine (including a swimmer's view as required) had a sensitivity of 83% and a specificity of 97%. The addition of open mouth (OM) and anteroposterior (AP) views detected all patients with unstable fractures except one man with a head injury who was unable to provide clinical clues to the diagnosis, but who suffered no additional harm as a result. A single lateral X-ray of the cervical spine is inadequate to exclude cervical spine injury in severely traumatized patients and the addition of OM and AP views still failed to identify unstable fractures in one of 385 patients in this series of MVC victims with GCS less than 15.(ABSTRACT TRUNCATED AT 250 WORDS)

Motor vehicle crashes remain a leading cause of death and injury in the industrialized world. Alcohol consumption is implicated as a major factor in fatal motor vehicle crashes (MVCs), but only poor estimates of blood alcohol concentrations among nonfatally injured crash victims are available. A 3-year study was undertaken at a Regional Trauma Unit to determine the demographics, injury severity, and alcohol positivity of motor vehicle crash victims. Between August 1, 1986 and July 31, 1989, 825 motor vehicle crash victims were available for study; 368 drivers were admitted to the unit within a period of 4 hours. Of 715 patients tested for alcohol, 31.0% were positive. A total of 333 drivers were tested for blood alcohol; 128 (38.4%) were positive. The mean blood alcohol concentration (BAC) at admission for the drivers was 145.6 mg/100 ml; the estimated mean BAC at crash was 180.9 mg/100 ml. The mean age of BAC positive drivers was 31.4 years, compared to a mean age in the BAC negative drivers of 35.2 years (p less than 0.02). Male patients represented 76.6% of the drivers, yet represented 83.6% of the BAC positive drivers (p less than 0.05). There was a marked seasonal variation in BAC positivity, with 46.1% of drivers positive during the summer months. Alcohol appears to be a significant factor in nonfatal MVCs.

Seatbelt usage has been consistently documented to decrease mortality and injury severity from motor vehicle crashes (MVC); however, conflicting results are available comparing mortality and injury severity, and blood alcohol positivity. Prospective testing on all MVC admissions showed that 51.5% of the non-belted, and 22% of the shoulder-belted drivers had a positive blood alcohol content (p less than 0.001). A comparison of belted and non-belted MVC drivers revealed a significantly higher mean length of stay (LOS) (p less than 0.05) and Injury Severity Score (ISS) (p less than 0.01) for the non-belted drivers. A comparison of groups positive and negative for blood alcohol revealed no significant differences in LOS or ISS, suggesting that these parameters are related to seatbelt use and not alcohol consumption.

Sunnybrook Medical Centre is a tertiary care teaching hospital situated in metropolitan Toronto. Its trauma unit, opened in June 1976, serves the inhabitants of metropolitan Toronto and the surrounding area (approximately 5 million). More than 3200 patients were admitted to the unit between 1976 and 1987. The criteria for admission were age at least 14 years and an Injury Severity Score (ISS) of 16 or greater, two or more significant injuries at anatomically discrete sites when the score on the Abbreviated Injury Scale was 3 or greater, or grade IV shock (systolic blood pressure of 80 mm Hg or less). The number of patients admitted annually to the unit increased over the study period. The survival rate also increased, from 76% in 1976 to 88% in 1987, although the average age and ISS of the patients remained unchanged. Less than 2% of the patients required long-term rehabilitative or chronic care. The patient profile is similar to that seen in other trauma centres in North America. The success of this program is largely the result of expeditious stabilization and transfer from referring hospitals coupled with early definitive surgical intervention.

A vasoactive peptide known to increase vascular permeability and corresponding to residues 30-43 of the human fibrinogen B beta-chain induced polymorphonuclear leukocyte emigration in rabbit skin in vivo. The leukocyte emigration was much stronger after 2 h than after 0.5 h. Addition of prostaglandin E2 (PGE2) did not influence the chemotactic activity, which might possibly be explained by a known PGI2 releasing capacity of this peptide. PGE2 enhanced the leukocyte emigration due to leukotriene B4.

We describe a procedure for treatment of thin-layer chromatographic serum lipid patterns so that they may be stained by dyes for evaluation by densitometry. After development of the chromatogram [Clin. Chem. 18, 384 (1972)] the plates are dried and sprayed with butyryl chloride. This esterifies the free cholesterol. After drying, the plate is treated with iodine monobromide, to add iodline to the double bonds. The triacylglycerols (triglycerides), cholesterol esters, free cholesterol, and phospholipids are now all in the form of esters with no unsaturated double bonds. The free fatty acids are also now saturated. The chromatogram is now stained with basic fuchsine in acetate buffer (0.1 mol/liter, pH 5.0). Excess stain is removed with a buffered solution of guanidine hydrochloride. Erythrosine B may also be used. With basic fuchsine the background will be a uniform pink. With erythrosine B the background is white, but the stain tends to be washed out of the free fatty acids. The chromatograms are evaluated by densitometry, with use of a 540-nm filter for basic fuchsine and a 520-nm filter for erythrosine B. The stained chromatograms and densitometric scans accurately represent the relative concentration of the various lipid fractions as compared to that of an internal standard, and correlate with the nature of the disease being explored.

Seaweed concentrate was applied to wheat plants either as a root drench or as a foliar spray. All seaweed treatments resulted in a marked increase in culm diameter. This increase was due mainly to an increase in cell size, especially of the vascular bundles. Seaweed concentrate also affected grain yield favourably. Similar observations resulting from other growth regulator usage and the significance of the findings are discussed., (Copyright © 1984 Gustav Fischer Verlag, Stuttgart. Published by Elsevier GmbH.. All rights reserved.)

A trauma centre must provide a system of care. This begins as soon as possible after the injury and continues until the patient returns to his usual daily activities. Because of necessity, such trauma centres deal with those who have serious or multiple injuries. Then it is important to provide early and appropriate care from the outset and sometimes before definitive management is undertaken. Care must be expeditious always as this reduces morbidity and mortality. We consider management to be divided into (a) before admission, (b) care in hospital, and, lastly (c) rehabilitation or other measures after discharge. This paper focuses on what we describe as the "golden hour" which is that crucial first hour after admission. Nevertheless, to achieve optimal results the whole system of care is vital. It is in that initial hour, however, that our radiologic colleagues are most clearly and actively involved.

Despite considerable advances in treatment in the last 20 years, trauma continues to be the main cause of disability and death for people under the age of 40 years. The outcome after injury has been improved by the introduction of advanced prehospital life support, early transfer and the establishment of specialized programs. Trauma care is governed by two underlying principles: early definitive management and a continuum of treatment from the time of injury to the return to the activities of daily life. Most important, a team approach is necessary in the treatment of the trauma patient. This requires the cooperation and participation of prehospital emergency personnel and referring hospitals as well as multidisciplinary collaboration within each trauma centre. There continue to be areas of neglect that prevent optimal trauma care and must be addressed.

A low dose technique has been recently proposed for tomographic studies of the lung, which makes use of a gamma camera to detect 90 degrees Compton-scattered photons from external planar gamma source. In this paper, we present a detailed Monte Carlo study of this technique. A 20 x 20 x 20 cm3 water phantom was simulated as a target and a large gamma camera equipped with an imaging collimator as a detector. The multiple scattering contamination of the single scattered signal was studied as a function of the source-detector geometry and of the incident energy in the range 100-500 keV. The multiple to single scatter ratio has an approximate 1/E0.7 dependence and increases almost linearly with the phantom depth and the transversal thickness at 90 degrees . Simulation has been also performed with a 16 x 16 x 10 cm3 sawdust phantom of 0.3 g/cm3 density; the Monte Carlo results agree to within a few percent with experimental data.

Citrated canine platelet rich plasma stimulated with ADP, thrombin, collagen and E. coli endotoxin demonstrated platelet aggregation when measured with Payton aggregometer. Following incubation with hydrocortisone sodium succinate (Solu-Cortef) the same platelet rich plasma did not undergo platelet aggregation when stimulated by these agents. Solu-Cortef added to platelet rich plasma during ATP, thrombin, collagen and endotoxin stimulated platelet aggregation resulted in a reversal of the optical density suggesting deaggregation. These in vitro observations support the beneficial effects observed when steroids are administered in vivo to experimental or clinical shock.

Primary and leakage x-ray spectra for typical clinical accelerators have been calculated using the EGS Monte Carlo code for 3 energies (6, 10 and 25 MeV) and 4 angles (0 degree, 45 degrees, 90 degrees and 135 degrees). Broad-beam transmission curves have been calculated for ordinary concrete using the MORSE program with the EGS spectra as input. A simple analytical model, which is shown to agree rather well with both experimental data and with the MORSE results, is presented and initial and subsequent tenth-value layers are extracted. Finally, the photon spectrum after the concrete shield is obtained with MORSE.

Two fatalities are reported following intralesional injection of BCG for immunotherapy of malignant melanoma. In both cases the terminal events were characterized by high fevers, major clotting defects, hypotension, and anuria, suggesting that the mechanism was hypersensitivity to BCG.

Monte Carlo calculations have been made to determine the energies delivered by photons and neutrons to the human body irradiated by collimated photon beams. The beams were monoenergetic and ranged from 100 keV to 40 MeV. The energy deposition in the body was sorted into two regions: inside and outside the irradiated volume. Most of the results obtained were for a beam size of 100 cm2 although some calculations were also made to 600 cm2 beams. The effect of beam size on energy deposition in the two regions was investigated for 60Co gamma rays. Graphs are presented which give the integral doses delivered by neutrons and photons to the two regions for therapy beams of various energies. These graphs can be used to calculate the integral doses which are delivered inside and outside the treatment volume for photon spectra from most medical accelerators. Calculations of energy deposition were also made for the spectra from two particular accelerators. These were done using Monte Carlo as well as by simply "folding" the spectra into the results for monoenergetic photons. The results obtained by both methods were in good agreement and indicated that the integral doses deposited outside the treatment volume by neutrons are more than two orders of magnitude smaller than those deposited by scattered photons.